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Thread: QwtPlotZoomer very slow

  1. #1
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    Default QwtPlotZoomer very slow

    Hi guys,

    thanks in advance. I'm using the QwtPlot and I represent the curve as a line, that connects the dots that are in my data set.

    The problem is that, the more points I have to represent, slower are the consecutive zooms on the plot. It takes long time to zoom the third time, and the app freezes.

    With simple plots (no more than 2000 points in the set) ther is no problem, but If I increase the number of points in the set, the graph, thena I cannot zoom several times.

    Any idea?

    I've seen the real_time example, where you can add a lot of points in the graph and then zoom. An It seems fast, so I dont know why mine takes long time

    Thanks!!

  2. #2
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    Default Re: QwtPlotZoomer very slow

    Solved. It was the AntiaAliasing property of the curve

  3. #3
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    Default Re: QwtPlotZoomer very slow

    QwtPlotCurve::ClipPolygons ?

    Uwe

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